Chain drill



, Nov, 22, 1938. D. H. GOODMAN CHAIN DRILL Filed March 2, 1936 2 Sheets-Sheet 1 I Dewe yHG oodman INVENT OR. v

Nov. 22, 1938. D H, O bMAN 2,137,940

CHAIN DRILL Filed March 2, 1936 2 Sheets-Sheet 2 Fig.2

D ewey H. 6 0001mm 7 I 1(NVEN'1TOR. BY I A ORNEY.

Patented Nov. 22, 1938 M UNITED STATES PATENT @FFECE.

1 p 2.12.1,940 i CHAIN paint 7 Dewey H. Goodman, Iowa Park, Tex. Application March 2, 1936, *S'erial No. 66,746

4 Claims.

The invention relates to boring tools and aims to provide a drill adapted to be power driven and portableand of atype to be held to the work "by a chain or equivalent means.

The invention provides a tool that may be driven from a distant point by an automobile or other suitable and convenient source of power, and which may be thrown into and out of ,a'ction at will, without stopping the motive ower? The invention furthermore provides a drill which admits of the bit being automatically thrown into and out of action by the pressure exerting means which, when applied, throws the bit into action and which, when released, throws the bit out of action.

A further purpose is the provision of a tool of the character aforesaid which allows changing of the bit at any time, when the tool is at rest or running, means being provided to release the 20 bit by tapping a drift or rod..

While the drawings illustrate a preferred embodiment of the invention, it is to be understood that in adapting the same to meet specific needs and requirements, the design may be varied and 25 changes in the minor details of construction may be resorted to within the scope of the invention as claimed, without departing from the spirit thereof.

For a full understanding of the invention and 30 the merits thereof, reference is to be had to the following description and the drawings hereto attached, in which:

Figure 1 is a View illustrative of an embodiment of the invention driven by a motor vehicle. 35 Figure 2 is an enlarged detail sectional view of the tool.

Figure 3 is a sectional detail on the line 3-3 of Figure 2.

Figure 4 is a detail section on the line 4--4 of 40 Figure 2.

Figure 5 is a view similar to Figure 4, on the line 5-5 of Figure 2.

Corresponding and like parts are referred to in the following description and designated in 45 the several views of the drawings by like reference characters.

' The tool embodies a frame consisting of a hollow body 6 closed at its top by a bonnet 6a and at one side by a plate 6b. A drive shaft 1 50 is mounted in the frame and is formed with an axial opening to receive a bit stock lb, drift rod 2|] and expansible spring l8. The upper portion of the shaft 1 is reduced to provide a shoulder Ir and receive a feed tube Iu, anti-friction bearings 5; 16 being interposed between the shoulder 11' and the lower. end of the tube lu. A bit chuck is provided at the lower end of the bit stock and consists of the usual tapered opening 1m to receive the tapered shank of a bit l5. The drift rod 26 has a limited play in the drive shaft 1 and bit stock and engages the shank of the bit IE to admit of releasing the bit by tapping upon the upper projecting end of the drift. The lower "portion of the bit stock lb has a loose fit in the I axial opening To of the drive shaft and its upper portion 1k is reduced and has a close fit in a portion of the axial opening. The expansible spring I8 engages the bit stock and normally urges it downwardly and disengaged from the drive shaft.

A square or non-circular portion ll, of the open- 15 ing I0 is adapted to receive a correspondingly shaped portion lg of the bit stock when the latter is in clutched engagement with the drive shaft. These elements 1] and lo constitute parts of a clutch which are normally held out of engagement by the spring l8 but which are in engagement when pressure is exerted through the feed member lu to throw the bit into action. The bit stock has alimited play determined by a stop 2| and an annular recess Ii, the part 2! being threaded into the drive shaft 1 and the recess 'li being formed in the bit stock.

A nut la retains the feed member lu on the drive shaft 1, a thrust bearing ls being interposed between the nut and the drive shaft. A longitudinal groove 'ld formed in a side of the part 111. receives the inner end of a screw l9 applied to the bonnet 6a and prevents turning of the feeder. Cog teeth 'lc formed in a side of the part 111, provide a rack which coacts with a pinion I6 fast to a shaft lfia mounted in the bonnet 6a. A bar I! adjustable in a projecting end of the shaft lBa provides a handle for exerting a variable pressure to apply the bit.

Gearing 8 and 9 is mounted in the frame 6 and imparts motion to the drive shaft 1 from a suitable source of power, as a motor vehicle 22. The bevel gear 8 is splined to the drive shaft 1 to admit of the latter moving longitudinally. The bevel gear 9 is keyed to a socket l0 mounted in a tubular extension of the plate 6b and retained in place by a nut H. A flexible shaft l2 transmits power from a suitable source and is protected by a covering l3. The shaft I2 is secured in any determinate way to the socket l0 and clamped to the axle of a motor vehicle 22 by fastening means 24, the drive wheel being jacked up, as indicated at 23.

Hooks [4 are applied to the frame 6 and engage links of a chain 25 to hold the drill to the work 5 26 when the tool is in operation. A groove 81) formed in a side of the shaft 1 receives a spline 8a which connects the shaft and bevel gear 8. When the tool is adjusted for action, power is transmitted thereto from asuitable source by the shaft l2 or other preferred and convenient means. Upon rotating shaft Ilia by means of the handle I], the bit I5 is advanced and, at the same time, the clutch |f1g is engaged and rotation of the bit effected. A counter-rotation of the shaft l6a relieves the feed pressure exerted on the bit I5 and permits disengagement of the clutch and the idling of the drive shaft 1 without the necessity of stopping the motive power. At this stage the bit l5 may be released, replaced, or adjusted. A tap on the drift rod 20 effects release of the bit as heretofore stated.

Having thus described the invention, what I claim is:

1. A boring tool comprising a frame, a drive shaft mounted therein for rotation and having a limited longitudinal movement therein, drive gearing splined to the drive shaft, a bit stock loosely mounted in the drive shaft and having an independent longitudinal movement therein, a clutch between the bit stock and drive shaft, a spring normally holding the clutch disengaged, a pressure member mounted on the drive shaft, and pressure exerting means for advancing the bit and throwing the clutch into engagement.

2. A boring tool comprising a frame, a drive shaft therein, a pressure member mounted on the drive shaft, coacting means between the frame and pressure member for advancing and retracting the latter, a bit stock slidably mounted within the drive shaft, a clutch disposed within the drive shaft and automatically operable by Work resistance to the tool feed, and a spring located in the drive shaft and normally holding the clutch disengaged.

3. A boring tool comprising a frame, a drive shaft therein, a pressure member mounted on the drive shaft, coacting means between the frame and pressure member for advancing and retracting the latter, means for preventing rotation of the pressure member relative to the frame, a bit stock slidable in the drive shaft, a clutch housed in the drive shaft and adapted to connect the bit stock thereto, and a spring disposed within the drive shaft and normally holding the bit stock disengaged from the drive shaft.

4. A boring tool comprising aframe, a drive shaft slidable in the frame, a pressure member carried by the drive shaft and held from rotation relative to the frame, means for moving the pressure member to control the feed, drive means mounted on the frame and splined to the drive shaft, a clutch and clutch disengaging spring within the drive shaft and housed thereby, and a drift rod passing through the drive shaft forv detaching a bit therefrom and having the clutch disengaging spring mounted thereon.

DEWEY H. GOODMAN. 

